TMP47C990E TOSHIBA [Toshiba Semiconductor], TMP47C990E Datasheet - Page 6

• Manufacturer Part Number: TMP47C990E
• Description: CMOS 4-bit Microcontroller
• Manufacturer: TOSHIBA [Toshiba Semiconductor]

TMP47C101/201
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2.3 H Register and L Register
The H register and L register are 4-bit general registers. They
are also used as a register pair (HL) for the data memory (RAM)
addressing pointer. The RAM consists of pages, each page
being 16 words long (1 word = 4 bits). The H register specifies
a page and the L register specifies an address in the page.
capability, implementing the execution of composite instruc-
tions. For example, [ST A, @HL+] instruction automatically in-
crements the contents of the L register after data transfer.
The L register has the auto-post-increment/decrement
Figure 2-4. Configuration of H and L Registers
Figure 2-3. Program Memory Map
instructions, the L register is also used to specify the bits cor-
responding to I/O port pins R73 through R40 (the indirect ad-
dressing of port bits by the L register).
During the execution of [SET @L], [CLR @L], or [TEST @L]
Example: To Write immediate values “5” and FH” to data
LD
ST
ST
memory addresses 10H and 11H.
HL, #10H
#5,@HL+
#0FH,@HL+ ;
;
;
TOSHIBA CORPORATION
HL 10
RAM [10
RAM [11
H
H]
H
] F
5
H
H
, LR LR + 1
, LR LR + 1